Heavy Metals Impact on Irrigated Vegetable Food Crops Consumed in Zaria

1,3*Yebpella G.G., 1,3A..M. Magomya; 1R. Odoh; 2U.U. Udiba; 1E. A. Kamba; 3I. Gandu,1
Page No. 197-204

Research on pollutants level in vegetables in relation to environmental pollution is imperative
considering the recent concerns about the pollution in rivers, streams, stagnant waters, and soils on
which the vegetables are grown and irrigated in Nigeria. Ten (10) samples each of vegetables, soil
and water were collected and analysed for Pb, Cd, Cr and Fe. The order of their occurrence in all
the samples is as follows: Cd < Cr < Pb < Fe. The metals were also found to be highest in soil
samples, lowest in water sample and in vegetable samples been the intermediary. Results of
correlation analysis conducted revealed positive correlation between Fe in vegetable and Pb, Cd,
Cr in soil also Fe in Water and Cr, Cd, Fe in vegetable but insignificant at p = 0.05. Transfer
factor was also determined and Cd was found to have the highest transfer factor of 0.91 followed by
Pb (0.87), Cr (0.83) and iron (Fe) with the lowest transfer factor of 0.18. When the result was
compared to food standard set by WHO/FOA, Cd, Pb, Cr and Fe levels in the three media were
found to be higher than the maximum permissible limit.